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H. E. Dudeney, Amusements in Mathematics (1917) No. 127 · Puzzles · Arithmetical puzzles

Simple Division

Sometimes a very simple question in elementary arithmetic will cause a good deal of perplexity. For example, I want to divide the four numbers, 701, 1,059, 1,417, and 2,312, by the largest number possible that will leave the same remainder in every case. How am I to set to work Of course, by a laborious system of trial one can in time discover the answer, but there is quite a simple method of doing it if you can only find it.

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H. E. Dudeney, Amusements in Mathematics (1917) · No. 127

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